for the star-forming complexes and higher σ and [ N II ]/ H-alpha surrounding the radio emission region , supporting interaction between the radio plasma and ambient gas . The two OH masers detected in IRAS F23199E are observed in the vicinity of these enhanced σ regions , supporting their association with the active nucleus and its interaction with the surrounding gas . The gas velocity field can be partially reproduced by rotation in a disk , with residuals along the north-south direction being tentatively attributed to emission from the front walls of a bipolar outflow .
The combination of HST images , VLA line spectroscopy , and Gemini IFU spectroscopy strongly indicates that , in this system , the OH megamaser sources are associated with the AGN rather than star formation .
Analysis of the inner regions of OH megamaser galaxies can contribute to our understanding the origin of these systems and provide insights into the star formation and galaxy evolution processes . Further adaptive optics observations with Gemini ’ s Nearinfrared Integral Field Spectrograph , as well as spectroscopic observations with integral field units of next generation telescopes , will allow a better understanding of the role AGN play in the gas emission of OH megamaser galaxies .
July 2018
Rogemar A . Riffel is an associate professor at Universidade Federal de Santa Maria - UFSM , Brazil . He can be reached at
rogemar @ ufsm . br
References
Skinner , C . J ., “ A starburst origin of the OHmegamaser emission from the galaxy Arp220 ,” Nature , 386 : 472 , 1997
Lo , K . Y ., “ Mega-masers and Galaxies ,” Annual Review of Astronomy and Astrophysics , 43 : 625 , 2005
Huang , Yong , et al ., “ OH Megamaser : dense gas & the infrared radiation field ,” Journal of Astrophysics and Astronomy , 39 : 34 , 2018
GeminiFocus
9
Figure 5 .
Observed H-alpha velocity field ( left ), rotating disk model ( center ), and residual between the two ( right ). The central cross marks the position of the nucleus , the white regions are masked locations where we were not able to fit the emission-line profiles , and the dotted lines represent the orientation of the line of nodes . The black contours in the residual map are from the 3-cm radio image with the same flux levels as shown in Figure 1 , and the white contours show radio contours at the 1.5 sigma level . The black asterisks labeled OH1 and OH2 mark the position of the maser sources .
for the star-forming complexes and higher
σ and [N II]/H-alpha surrounding the radio
emission region, supporting interaction
between the radio plasma and ambient
gas. The two OH masers detected in IRAS
F23199E are observed in the vicinity of these
enhanced σ regions, supporting their as-
sociation with the active nucleus and its in-
teraction with the surrounding gas. The gas
velocity field can be partially reproduced by
rotation in a disk, with residuals along the
north-south direction being tentatively at-
tributed to emission from the front walls of
a bipolar outflow.
The combination of HST images, VLA line
spectroscopy, and Gemini IFU spectroscopy
strongly indicates that, in this system, the
OH megamaser sources are associated with
the AGN rather than star formation.
Analysis of the inner regions of OH mega-
maser galaxies can contribute to our under-
standing the origin of these systems and
provide insights into the star formation and
galaxy evolution processes. Further adap-
tive optics observations with Gemini’s Near-
infrared Integral Field Spectrograph, as well
as spectroscopic observations with integral
field units of next generation telescopes,
will allow a better understanding of the role
AGN play in the gas emission of OH mega-
maser galaxies.
July 2018
Hekatelyne Carpes is a recent PhD graduate at
Universidade Federal de Santa Maria - UFSM,
Brazil. She can be reached at:
[email protected]
Rogemar A. Riffel is an associate &fW76"@VfW'6FFRfVFW&FR6F&Te4'&R6&R&V6VBB&vV$Vg6' &VfW&V6W06W"2( 7F&'W'7B&vbFRЦVv6W"V֗76g&FRv'##( ФGW&R3cCs"p( Vv6W'2BvW2( V&WfWrb7G&גB7G&672C3c#R#PVrŖrWB( Vv6W#FV6Rv0bFRg&&VB&FFfVB( W&b7G&Ч672B7G&ג33B#vV֖f7W0fwW&RR'6W'fVBfV6GfVBVgB&FFrF6FV6VFW"B&W6GV&WGvVVFRGv&vBFR6VG&7&70&2FR6F`FRV6WW2FRvFP&Vv2&R6[email protected]6F2vW&RvPvW&RB&RFfBFPV֗76ƖR&fW2BFRFGFVBƖW0&W&W6VBFR&VFFbFRƖRbFW2FP&66FW'2FP&W6GV&Rg&ЧFR26&FvPvFFR6RfWWfV026vfwW&RBFRvFR6FW'06r&F6FW'2@FRR6vWfVFP&67FW&62&V[email protected]B"&FP6FbFR6W 6W&6W2࣐